Effects of acute cartilaginous injury on serum and cartilage lysozyme levels.

Acute cartilage degradation was produced in rabbits by the intravenous injection of crude papain. This resulted in a significant rise in serum lysozyme in 97% of the animals, as well as a fall in the residual lysozyme content of auricular and costal cartilage. The rise in serum lysozyme paralleled the rise in serum chondroitin sulfate. The source of the rise in lysozyme appeared to be the release of extracellular, nonlysosomal lysozyme from the cartilage matrix. Serum lysozyme elevation in arthritic disorders may reflect cartilage degradation.